As a way of thinking, sustainability is well suited to forestry, since forests have traditionally been seen as an asset that will benefit several generations. From a forest owner’s point of view, the most essential factor in climate change mitigation is ensuring that forests remain viable.
“Making sure that forests are in a fit state to grow is key. When trees fall, the carbon that has been stored in them is released,” says Jyrki Kangas, Professor of Forest Bioeconomy at the University of Eastern Finland.
The trees and soil in forests absorb carbon dioxide and act as carbon reservoirs. In principle, extending forest turnover times improves the carbon balance, but trees cannot be left to grow infinitely. The optimal time for harvesting, considering both forest productivity and the climate, is before tree growth begins to slow down and trees become more susceptible to damage. From the point of view of carbon binding, it is essential that forests produce wood as efficiently as possible. The faster a forest grows after a regeneration felling, the faster it will begin to store carbon.
“Forest owners have done a lot of good work over the years,” Kangas says. “The triumphant progress of Finnish forestry has also been a success story in climate change mitigation, both from the point of view of carbon sinks and the use of renewable raw materials.”
A better world for generations to come
Forest owners can do a lot to help maintain the viability of forests and minimize their susceptibility to damage. However, it is not always easy to perform forest management activities in a manner that is optimal for the climate. In Southern Finland, for example, forests are dominated by spruce, which reduces their albedo or reflection of solar radiation. This means that the thermal radiation of the sun is absorbed by the forest instead of being reflected back to space. From a climate point of view, spruce is used too much, but there is a natural explanation for its popularity: elks are greedy for birch and pine saplings.
“If 90% of a sapling stand where the saplings have only reached a height of half a metre is gobbled up by elks, who in their right mind would want to plant more birch trees,” Kangas laughs. His example is a true story.
“The important thing is to see forests as an asset that will be passed on to future generations, which comes naturally to forest owners. We should try to ensure that our children will live in a better world.”
Finnish forests grow back
Wood is a renewable resource. This means that when a forest is regenerated after a regeneration felling, the same hectare of forest land will soon begin to store carbon from the atmosphere. Wood can also be used to replace fossil-based products.
“When oil, coal or natural gas is burnt or used as a raw material, carbon that has been stored for millions of years is released into the atmosphere,” says Sami Oksa, Director, Stakeholder Relations, UPM Forest.
In the short term, felling trees releases carbon dioxide into the atmosphere, but the regenerated forest soon stores new carbon. According to calculations made by Natural Resources Institute Finland (Luke), a regenerated hectare of forest regains its status as a carbon sink after 17 years — and then continues as one for the entire life cycle of the trees. Products made of wood and wood-based raw materials are also an excellent means for storing carbon.
Amidst climate change discussions, forest owners may wonder whether using their forests is sustainable from a climate point of view. However, the felling of rain forests and the felling of Finnish forests are two very different phenomena. In Finland, forests are regenerated and forest land remains forest land even after felling.
Strong growth continues
In Finnish forestry, 100% of the wood is always used. Any wood that cannot be used as sawn timber or fibre is burnt and turned into energy. As a result of advanced forestry, the annual growth of trees has exceeded the volume of felling and natural losses in Finland since the 1960s. This means that our forests form a significant carbon sink. Currently, the annual growth of trees is some 107 million cubic metres, while the volume of felling and natural losses amounts to 85 million cubic metres.
Increasing the wood yield further will, however, require that we take good care of our forests. According to research, managed forests are better carbon sinks than unmanaged forests. Canada, for instance, has huge forest areas, but forest management and thinning are relatively rare.
“Due to lack of forest management, Canadian forests are currently sources of carbon emissions instead of carbon sinks because of extensive insect damage. When trees die and are left to rot, forests no longer bind as much carbon as before,” Oksa explains.
Wood is the material of the future
Taking a holistic approach to sustainability and bioeconomy entails optimizing ecological, social and economic sustainability. From the point of view of climate change, it is essential to reduce fossil emissions, store carbon dioxide, for example in forests, and find products and raw materials to replace fossil materials.
“In the long term, the objective should naturally be for fossil carbon to remain below the surface of the Earth,” says Johanna Buchert, President and CEO of Luke.
According to Buchert, the performance of the entire forest industry is dependent on companies being able to act in an ecologically sustainable way and create innovative products with high added value.
“The strong growth of Finnish forests has been achieved because of forest owners who have taken good care of their forests. However, forest management has also been neglected in some forests, and forest ownership has seen a shift in recent decades. Forest owners are becoming urbanized and they are not necessarily as committed to their forest assets as previous generations.”
Forest bioeconomy offers excellent opportunities for producing materials that can replace fossil raw materials. Wood construction and the use of wood-based textiles to replace cotton are examples of environmentally friendly phenomena.
“Nevertheless, the greatest challenge in preventing climate change is the global increase in consumption and getting consumers to demand sustainable alternatives and renewable products,” says Buchert.